In general, stricture of organs or blood vessels may be caused and internal secreting fluid cannot smoothly flow due to a disease in a human body and operations, and several parts of a human body cannot normally work due to stricture of organs and blood vessels.
When internal secreting fluid cannot smoothly flow, various kinds of plastic stents are used, and particularly, when stricture of the bile duct and ERBD (Endoscopic retrograde Biliary Drainage) occurs, an operator inserts a plastic stent through an endoscope so that bile and secretion are smoothly discharged.
Further, ERCP (Endoscopic retrograde cholangiopancreatography) is an examination that inserts an endoscope into the duodenum and examines diseased parts of the bile duct and the pancreatic duct through a small hole called the ampulla of Vater. However, the ampulla that is cut by a knife called Sphinctenotome through EST (endoscopic sphincterectomy) after an endoscope is inserted for examining the bile duct and the pancreatic duct may be inflamed or may be in danger of secondary complications (cholangitis or pancreatitis).
A procedure of inserting a plastic stent is performed to prevent such secondary complications.
There are various kinds of plastic stents, including the shapes in which both ends are rolled in the same direction or different directions or barbs are formed at both ends in accordance with the usage or the procedure places, and the bodies are cylindrical in most cases.
According to the common way of the related art that inserts a plastic stent into a body for a procedure, a double pipe of a guide catheter and a push pipe moving forward/backward along the guide catheter is used, in which a plastic stent is fitted in the guide catheter partially exposed and inserted into a lumen and then the push pipe is moved forward to operate on a desired portion.
An operation tool such as specific forceps, which pushes or pulls the plastic stent, is used to adjust, the position of the plastic stent.
However, when a guide catheter is used, its size should be changed in accordance with the kind or size of a plastic stent and it is difficult to adjust the position after an operation.
In order to solve this problem, a way of coupling a plastic stent to the front of a guide catheter with a suture, inserting the stent into a lumen of a body and moving the guide catheter to the accurate operation position, and then separating the plastic stent from the guide catheter by untying the suture has recently been proposed.
However, this operation type of coupling a plastic stent to a guide catheter with a suture can ensure stability because the guide catheter and the plastic stent are coupled in a single unit, but there is a problem in that it is required to untie the suture to perform an operation and readjust the position of the plastic stent after removing the suture.
There is a strong need of an operation tool that can adjust the position for an operation of a plastic stent, adjust the position after the operation, remove a portion of a tissue like forceps, and excise a tissue like a snare, using an operation mechanism moving forward/backward.